SIMBAD references

Effective temperatures T_eff, surface gravities logg and interstellar extinctions A_V are found for 107 B stars. Distances d of the stars, which are based on the derived T_eff, logg and A_V values, show good agreement with those obtained from the Hipparcos parallaxes. Comparing the T_eff and logg values with evolutionary computations, we infer masses, radii, luminosities, ages and relative ages of the stars. Empirical relations between the T_eff and logg parameters, on the one hand, and the photometric indices Q, [c₁] and β, on the other hand, are constructed; these relations give a fast method for the T_eff and logg estimation of early and medium B stars. Inclusion of the infrared J, H and K colours into the T_eff, logg and A_V determination shows that (i) the T_eff and logg parameters are altered only slightly; (ii) the A_V value is rather sensitive to these colours, so an accuracy better than 0.05mag in the JHK data is necessary for precise A_V evaluation.